Does the use of surgical face masks reduce postoperative infections in traumatic wounds sutured outside hospital? A randomized study at a Norwegian casualty center

OBJECTIVE

To investigate if wearing surgical face mask by doctors and nurses during suturing of traumatic wounds has any impact on postoperative infection rate.

DESIGN

Randomized controlled study with masked or unmasked health personnel groups.

SETTING

A Norwegian Minor Injury Department.

SUBJECTS

Adult patients with traumatic wounds sutured at the clinic between 7 October 2019 and 28 May 2020.

MAIN OUTCOME MEASURES

Postoperative infections of sutured wounds.

RESULTS

One hundred and sixty-five patients with 176 wounds were included in the study. Nine out of 88 wounds (10.2%) in the masked group and 11 out of 88 wounds in the unmasked group (12.5%) had a wound infection.

CONCLUSIONS

Despite a higher percentage of postoperative infections in the unmasked than in the masked group (12.5% versus 10.2%), the difference was not statistically significant (p = .6). This might imply that the use of facemasks during suture of traumatic wounds in an outpatient setting does not significantly reduce the number of infections. However, due to the covid pandemic, the study had to be prematurely stopped before the planned number of participants had been recruited (n = 594). This increases the risk of type II error.

Effects of no mask, a surgical mask and a fabric buff on peripheral oxygenation saturation during moderate intensity exercise: a randomised cross-over study

Background

Mask-wearing caused significant reductions in coronavirus disease 2019 (COVID-19) transmission. We aimed to determine whether face mask-wearing during exercise caused reductions in peripheral oxygen saturation (SpO2) and whether it affected secondary physiological measures [end-tidal carbon dioxide (EtCO2), respiratory rate (RR), heart rate (HR), expired breath temperature (EBT)]. Subjective measurements included ratings of perceived exertion (RPE), ratings of perceived breathlessness (RPB), and symptomology.

Methods

A randomised cross-over trial examined no mask (NM), surgical mask (SM) and a buff mask (BM). Thirty participants (30-45 years) cycled at 60% power output for 30 min in three exercise sessions, 24 h apart, within 6 days. Each session recorded all measures at resting baseline (T0), 9 min (T1), 18 min (T2), and 27 min (T3). Dependent statistical tests determined significant differences between masks and time-points.

Results

SpO2 decreased for SM and BM between T0 compared to T1, T2 and T3 (all P<0.005). BM caused significant reductions at T1 and T2 compared to NM (P<0.001 and P=0.018). Significant changes in EtCO2 and EBT occurred throughout exercise and between exercise stages for all mask conditions (P<0.001). As expected for moderate intensity exercise, RR and HR were significantly higher during exercise compared to T0 (P<0.001). RPB significantly increased for each condition at each time point (P<0.001). RPE was not significant between mask conditions at any exercise stage.

Conclusions

SM and BM caused a mild but sustained reduction in SpO2 at commencement of exercise, which did not worsen throughout short (<30 min) moderate intensity exercise. Level of perception was similar, suggesting healthy people can wear masks during moderate exercise and activities of daily living.

Investigating effects of FFP2 wearing during physical activity on gas exchange, metabolism and affective state using a randomized controlled trial

Concerns are repeatedly raised about possible adverse respiratory effects of wearing filtering face pieces (FFP) during physical activity. This study compared the impact of FFP type 2 (NF95) on pulmonary function, blood gas values, metabolism and discomfort during light, moderate and vigorous physical activity. Healthy adults (n = 13; 6 females, 7 males; mean 31.3, SD 5.5 years) participated in this randomized two-armed (Ergometer cycling with a FFP type 2 vs. no mask) crossover trial. Baseline cardiopulmonary exercise testing and two interventions (masked and unmasked ergometer cycling 40%, 50% and 70% VO2max, 10 min each) were separated by 48 h washout periods. Spiroergometric data (End tidal carbon dioxide partial pressure PetCO2; breathing frequency; inspiration time), blood gas analysis outcomes (capillary carbon dioxide partial pressure, pCO2) and subjective response (Breathing effort and perceived exertion) were contrasted between conditions using ANOVAs. All participants completed the crossover trial, seven started with the FFP2 condition (No adverse events or side effects). FFP2 decreased breathing frequency, prolonged inspiration time, increased perceived breathing effort and PetCO2 (p < .05). Blood pCO2 in millimetres mercury increased during exercise with 50%VO2max (mean 36.67, SD 3.19 vs. mean 38.46, SD 2.57; p < .05) and 70%VO2max (35.04, 2.84 vs. 38.17, 3.43; p < .05) but not during exercise with 40%VO2max (36.55, 2.73 vs. 38.70). Perceived exertion was not affected (p > 0.05) by mask wearing. Conclusion: Mask-induced breathing resistance decreased respiratory performance and limited pulmonary gas exchange. While FFP2 affected subjective breathing effort per se, invasive diagnostics showed that statistically significant metabolic effects are induced from moderate intensity upwards. Trial registration: DRKS-ID: DRKS00030181, Date of registration: 05/09/2022 (German Register for Clinical Trials).

Effect of Facemask in Congenital Central Hypoventilation Syndrome

INTRODUCTION

Congenital central hypoventilation syndrome (CCHS) is a rare genetic disorder with a mutation in the PHOX2B gene. Patients need ventilatory support by noninvasive ventilation or tracheostomy to treat alveolar hypoventilation. Patients with CCHS have a defect in chemosensitivity signal integration. Recently, due to the COVID-19 pandemic, the entire world has had to get used to wearing medical masks (MM).

OBJECTIVES

The aim of the study was to evaluate the effect of an MM on gas exchange and to determine the role of central and peripheral chemoresponsiveness on the partial pressure of transcutaneous carbon dioxide (PtcCO2) in patients with CCHS wearing an MM.

METHODS

This study was based on the analysis of recordings obtained without and with an MM during hospitalization and was conducted to assess the impact of MM on PtcCO2 and SpO2 recordings with the SenTec Digital Monitor and their relationships with peripheral CO2 chemosensitivity obtained during tidal breathing measurement and with the hypercapnic hyperoxic ventilatory response.

RESULTS

Sixteen patients were included (13 boys) and were 10.2 (7.5; 18.5) years old. The use of an MM had a negative impact on gas exchange in patients with CCHS. The median PtcCO2 increased significantly. Peripheral chemosensitivity correlated with MM-induced PtcCO2 changes (R = -0.72, p = 0.005), but central chemosensitivity (the hypercapnic ventilator response slope) did not (R = -0.22, p = 0.510).

CONCLUSION

The use of an MM had a negative impact on gas exchange in patients with CCHS.

Impact of wearing a surgical facemask during exercise on dyspnea in patients with chronic pulmonary infections: A randomized crossover study

BACKGROUND

Wearing facemasks in public is effective in preventing viral transmission. However, no study has evaluated the impact of wearing facemasks during exercise on dyspnea in patients with chronic pulmonary infections from multifaceted aspects, including sensory qualities and emotional responses. The aim of this study was to evaluate facemask-related dyspnea during exercise in this patient population.

METHODS

We conducted a randomized crossover study involving adult patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) or bronchiectasis who participated in exercise sessions, both with (mask-on) and without (mask-off) surgical facemasks. The sensory and emotional dimensions of dyspnea during each exercise session were assessed using the Multidimensional Dyspnea Profile. Statistical analyses were performed to identify factors associated with worsening scores for each dimension.

RESULTS

Thirty-four patients (mean age [standard deviation]: 71.6 [8.6] years) were included in the analysis. The median [interquartile range] total scores for the sensory and emotional dimensions of dyspnea were 3.5 [1, 9.5] (mask-off) vs. 10 [5.5, 23.8] (mask-on) (P < 0.001) and 0 [0, 5] (mask-off) vs. 3 [0.8, 10.3] (mask-on) (P = 0.115), respectively. "Air hunger" was the primary sensory descriptor of mask-related dyspnea. Vital capacity (VC) < 80% of the predicted value was a significant risk factor for worsening sensory dimension scores when wearing masks (odds ratio [95% confidence interval]: 5.5 [1.16-26.1], P = 0.038).

CONCLUSIONS

The findings of this study indicate that patients with NTM-PD or bronchiectasis, particularly those with VC <80% of the predicted value, are likely to experience the sensory dimension of dyspnea during exercise while wearing surgical facemasks.

Soft tissue evaluation after maxillary protraction with RPE or with the ALT-RAMEC protocol : A controlled 3D study

PURPOSE

To evaluate soft tissue changes following maxillary protraction with different expansion protocols using three-dimensional (3D) stereophotogrammetry.

METHODS

Pretreatment (T0) and postprotraction (T1) stereophotogrammetry and lateral cephalometric images of skeletal class III patients were included in this retrospective study. In all, 32 patients were treated either with a combination of rapid palatal expansion and facemask (RPE/FM; n = 16; mean age: 9.94 ± 0.68 years) or with alternate rapid maxillary expansion and constriction together with a facemask (Alt-RAMEC/FM; n = 16; mean age: 9.74 ± 1.35 years). As a control group 16 untreated patients were recruited (mean age: 9.46 ± 0.8 years). For superimpositioning of the 3D images taken at T0 and T1, the face was divided into defined regions and 3D and differences between the groups were evaluated using 3‑matic software (Materialise Europe, Leuven, Belgium). Cephalometric analyses were also performed.

RESULTS

While the increases in the cephalometric parameters SNA and ANB were significantly greater in the treatment groups, the value for SNB also increased in the control group (p < 0.05). The results of the stereophotogrammetry analyses demonstrated that the mean changes in the RPE/FM and in the Alt-RAMEC/FM groups were significantly different for the midface compared to the control group (0.33 ± 0.26 mm, 0.3 ± 0.31 mm, 0.1 ± 0.18 mm). The maximum positive, negative, and mean changes were also significantly different between the treatment and control groups for the upper lip (p < 0.05). For the lower lip and the chin significant backward movements in the RPE/FM as well as in the Alt-RAMEC/FM group (-1.06 ± 1.26 mm, -0.68 ± 0.45 mm) were observed, while the control group (0.09 ± 0.53 mm) presented changes in the opposite direction. Regarding soft tissue changes, no significant differences were found between the RPE/FM and Alt-RAMEC/FM groups.

CONCLUSION

Both treatment protocols improved the soft tissue profile due to a forward movement of the midface and the upper lip, and a backward movement of the lower lip and chin, compared to the control group.

A novel N95 respirator with chitosan nanoparticles: mechanical, antiviral, microbiological and cytotoxicity evaluations

BACKGROUND

It is known that some sectors of hospitals have high bacteria and virus loads that can remain as aerosols in the air and represent a significant health threat for patients and mainly professionals that work in the place daily. Therefore, the need for a respirator able to improve the filtration barrier of N95 masks and even inactivating airborne virus and bacteria becomes apparent. Such a fact motivated the creation of a new N95 respirator which employs chitosan nanoparticles on its intermediate layer (SN95 + CNP).

RESULTS

The average chitosan nanoparticle size obtained was 165.20 ± 35.00 nm, with a polydispersity index of 0.36 ± 0.03 and a zeta potential of 47.50 ± 1.70 mV. Mechanical tests demonstrate that the SN95 + CNP respirator is more resistant and meets the safety requisites of aerosol penetration, resistance to breath and flammability, presenting higher potential to filtrate microbial and viral particles when compared to conventional SN95 respirators. Furthermore, biological in vitro tests on bacteria, fungi and mammalian cell lines (HaCat, Vero E6 and CCL-81) corroborate the hypothesis that our SN95 + CNP respirator presents strong antimicrobial activity and is safe for human use. There was a reduction of 96.83% of the alphacoronavirus virus and 99% of H1N1 virus and MHV-3 betacoronavirus after 120 min of contact compared to the conventional respirator (SN95), demonstrating that SN95 + CNP have a relevant potential as personal protection equipment.

CONCLUSIONS

Due to chitosan nanotechnology, our novel N95 respirator presents improved mechanical, antimicrobial and antiviral characteristics.

An optimal control model for Covid-19 spread with impacts of vaccination and facemask

A non-linear system of differential equations was used to explain the spread of the COVID-19 virus and a SEIQR model was developed and tested to provide insights into the spread of the pandemic. This article, which is related to the aforementioned work as well as other work covering variations of SIR models, Hermite Wavelets Transform, and also the Generalized Compartmental COVID-19 model, we develop a mathematical control model and apply it to represent optimal vaccination strategy against COVID-19 using Pontryagin's Maximum Principle and also factoring in the effect of facemasks on the spread of the virus. As background work, we analyze the mathematical epidemiology model with the facemask effect on both reproduction number and stability, we also analyze the difference between confirmed COVID-19 cases of the Quarantine class and anonymous cases of the Infectious class that is expected to recover. We also apply control theory to mine insights for effective virus spread prevention strategies. Our models are validated using Matlab mathematical model validation tools. Statistical tests against data from Jordan are used to validate our work including the modeling of the relation between the facemask effect and COVID-19 spread. Furthermore, the relation between control measure ξ, cost, and Infected cases is also studied.

Support for regulation versus compliance: Face masks during COVID-19

Objectives

Wearing masks could still be one of the few non-pharmaceutical interventions for controlling the pandemic. There are people who wear them and people who don't, but this framing is overly simplistic. We aim to chart the contradictions in attitudes and behavior regarding mask wearing and describe the messaging challenge that these generate.

Study design

Our data come from a survey administered to a nationally representative sample of 2000 respondents from the YouGov panel of US households in August-September 2020.

Methods

Respondents were asked whether they wear a facemask when they go outside their home since the COVID-19 epidemic began and whether they support or oppose your municipal government passing mask wearing regulation. We also collected respondents' demographic and economic characteristics, knowledge regarding the facts of COVID-19 and political ideology.

Results

A substantial majority of Americans (60%) both favor a masking requirement and are themselves wearing masks, while 13% oppose a mask mandate and do not wear masks. In contrast, 17% of Americans oppose a mask mandate but are currently wearing one, while 10% do not wear a mask but favor a mask mandate. These two groups are distinctively different from one another and the other groups in their socioeconomic characteristics, risk perception and political beliefs.

Conclusions

Our study offers a better understanding of the mismatch between mask wearing behavior and attitude toward the mask mandate, which will help the public health authorities to devise policies regarding mask wearing as an effective intervention to manage the pandemic.

Determining the filtration effectiveness of non-standard respiratory protective devices by an ad-hoc laboratory methodology

The recent pandemic caused by COVID-19 profoundly changed people's habits. Wearing a face mask has become usual in everyday life to reduce the risk of infection from airborne diseases. At the beginning of the pandemic, the massive request of surgical or filtering face piece (FFP) masks resulted in a global shortage of these devices for the most exposed people, such as healthcare workers. Due to this high demand for respiratory protective devices, many industrial plants have partly converted to the production of face masks using adapted materials and not complying with any specific regulation (non-standard respiratory protective devices or community masks). In this work, an ad-hoc laboratory methodology has been developed to evaluate the filtration efficiency of the materials that compose the community masks using specific instrumentation. The instrumentation consists of three main tools: an aerosol generator, a specifically designed measuring chamber, and an optical particle sizer (OPS) for the measurement of aerosol concentration. The generated aerosol was sent into the measuring chamber, divided into two separate sections by the respiratory mask. The OPS measured the aerosol mass concentration upstream and downstream of the respiratory mask, and from the concentration difference the filtration efficiency was evaluated. The proposed methodology has been validated by evaluating the particle filtration efficiency (PFE) of certified respiratory masks and was then applied for the evaluation of the filtration efficiency of different types of non-standard or community masks to analyze their effectiveness in protecting from the risk of infection of airborne diseases.

Comparison of changes in the nasal cavity, pharyngeal airway, and maxillary sinus volumes after expansion and maxillary protraction with two protocols: Rapid palatal expansion versus alternate rapid maxillary expansion and constriction

Objective

To evaluate and compare a series of volume changes in the nasal cavity (NC), nasopharynx, oropharynx, and maxillary sinuses (MS) in growing Class III patients after either rapid palatal expansion (RPE) or alternate rapid maxillary expansion and constriction (Alt-RAMEC) followed by facemask (FM) therapy, by using conebeam computed tomography (CBCT).

Methods

Forty growing Class III patients were retrospectively selected and divided into two matched groups: RPE/FM (14 females, 6 males; mean age, 9.66 ± 1.23 years) and Alt-RAMEC/FM groups (14 females, 6 males; mean age, 10.28 ± 1.45 years). The anteroposterior and vertical displacements of Point A, the volumes of the NC, nasopharyngeal, oropharyngeal, and MS were measured at different time points: pretreatment (T1), postexpansion (T2), and postprotraction (T3).

Results

Both groups demonstrated significant maxilla advancement (by 1.3 mm) during expansion, with a statistically significant intergroup difference during protraction (RPE/FM, 1.1 mm; Alt-RAMEC/FM, 2.4 mm; p < 0.05) and throughout the treatment (RPE/FM, 2.4 mm; Alt-RAMEC/FM, 3.7 mm; p < 0.05). NC and nasopharyngeal airway volumes increased significantly in both groups after expansion, protraction, and treatment. The oropharyngeal and MS volumes increased in both groups after protraction and post-treatment. However, no volumetric differences were observed between the two groups.

Conclusions

There was no significant difference in airway volume changes, including NC, nasopharyngeal, oropharyngeal airway, and MS, between RPE/FM and Alt-RAMEC/FM groups at different time points. Although there was significantly more forward movement after protraction in the Alt-RAMEC/FM group, the difference was deemed too small to be clinically relevant.

A Novel Vision of Reinforcing Nanofibrous Masks with Metal Nanoparticles: Antiviral Mechanisms Investigation

Prevention of spreading viral respiratory disease, especially in case of a pandemic such as coronavirus disease of 2019 (COVID-19), has been proved impossible without considering obligatory face mask-wearing protocols for both healthy and contaminated populations. The widespread application of face masks for long hours and almost everywhere increases the risks of bacterial growth in the warm and humid environment inside the mask. On the other hand, in the absence of antiviral agents on the surface of the mask, the virus may have a chance to stay alive and be carried to different places or even put the wearers at risk of contamination when touching or disposing the masks. In this article, the antiviral activity and mechanism of action of some of the potent metal and metal oxide nanoparticles in the role of promising virucidal agents have been reviewed, and incorporation of them in an electrospun nanofibrous structure has been considered an applicable method for the fabrication of innovative respiratory protecting materials with upgraded safety levels.

Graphical Abstract

Post-pandemic micro/nanoplastic pollution: Toward a sustainable management

The global health crisis caused by the COVID-19 pandemic has resulted in massive plastic pollution from the use of personal protection equipment (PPE), with polypropylene (PP) being a major component. Owing to the weathering of exposed PPEs, such contamination causes microplastic (MP) and nanoplastic (NP) pollution and is extremely likely to act as a vector for the transportation of COVID-19 from one area to another. Thus, a post-pandemic scenario can forecast with certainty that a significant amount of plastic garbage combined with MP/NP formation has an adverse effect on the ecosystem. Therefore, updating traditional waste management practices, such as landfilling and incineration, is essential for making plastic waste management sustainable to avert this looming catastrophe. This study investigates the post-pandemic scenario of MP/NP pollution and provides an outlook on an integrated approach to the recycling of PP-based plastic wastes. The recovery of crude oil, solid char, hydrocarbon gases, and construction materials by approximately 75, 33, 55, and 2 %, respectively, could be achieved in an environmentally friendly and cost-effective manner. Furthermore, the development of biodegradable and self-sanitizing smart PPEs has been identified as a promising alternative for drastically reducing plastic pollution.

Energy-saving COVID-19 biomedical plastic waste treatment using the thermal - Catalytic pyrolysis

The rate of Biomedical waste generation increases exponentially during infectious diseases, such as the SARS-CoV-2 virus, which burst in December 2019 and spread worldwide in a very short time, causing over 6 M casualties worldwide till May 2022. As per the WHO guidelines, the facemask has been used by every person to prevent the infection of the SARS-CoV-2 virus and discarded as biomedical waste. In the present work, a 3-ply facemask was chosen to be treated using the solvent, which was extracted from the different types of waste plastics through the thermal-catalytic pyrolysis process using a novel catalyst. The facemask was dispersed in the solvent in a heating process, followed by dissolution and precipitation of the facemask in the solvent and by filtration of the solid facemask residue out of the solvent. The effect of peak temperature, heating rate, and type of solvent is observed experimentally, and it found that the facemask was dissolved completely with a clear supernate in the solvent extracted from the (polypropylene + poly-ethylene) plastic also saved energy, while the solvent from ABS plastic was not capable to dissolute the facemask. The potential of the presented approach on the global level is also examined.

Face mask and medical waste generation in the City of Baguio, Philippines: its current management and GHG footprint

The daily use of facemask to prevent virus transmission increases the negative effect on the environment because of improper waste disposal. Due to the absence of baseline data, the impact of facemask and medical waste generation, as well as the community's management practice, should be studied to avoid further environmental degradation. In this study, we surveyed 384 respondents and conducted computational analysis to provide an overview of the household's facemask usage and ecological footprint in combating Covid-19. Results showed that most respondents (48.7%) use two facemasks per day. Thus, an estimated 417,834 facemasks are disposed daily, generating 3,585 kg/day of additional waste. The average medical waste of Covid-infected individuals is 3.29 kg per day per capita. This yields 22,438 kg. of CO₂ eq., which could contribute to the global warming potential; however, there is also a potential recovery of 61.572 gigajoules of energy for power generation. Most respondents are aware of proper facemask waste management practices, but some lacks application regarding responsible waste disposal. Despite the contribution of facemask to the overall solid waste generation, the city's current management remains a challenge since disposable facemasks are potentially mixed with other types of waste from its storage, collection, and disposal.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10163-023-01601-2.

Patient safety implications of wearing a face mask for prevention in the era of COVID-19 pandemic: a systematic review and consensus recommendations

In the past, the use of face masks in western countries was essentially limited to occupational health. Now, because of the COVID-19 pandemic, mask-wearing has been recommended as a public health intervention. As potential side effects and some contraindications are emerging, we reviewed the literature to assess the impact of them in daily life on patient safety and to provide appropriate guidelines and recommendations. We performed a systematic review of studies investigating physiological impact, safety, and risk of masks in predefined categories of patients, which have been published in peer-reviewed journals with no time and language restrictions. Given the heterogeneity of studies, results were analyzed thematically. We used PRISMA guidelines to report our findings. Wearing a N95 respirator is more associated with worse side effects than wearing a surgical mask with the following complications: breathing difficulties (reduced FiO₂, SpO₂^, PaO₂ increased ETCO₂, PaCO₂), psychiatric symptoms (panic attacks, anxiety) and skin reactions. These complications are related to the duration of use and/or disease severity. Difficulties in communication is another issue to be considered especially with young children, older person and people with hearing impairments. Even if benefits of wearing face masks exceed the discomfort, it is recommended to take an "air break" after 1-2 h consecutively of mask-wearing. However, well-designed prospective studies are needed. The COVID-19 pandemic could represent a unique opportunity for collecting large amount of real-world data.

Behavioral responses for facemask use messages to prevent COVID-19 among residents of Bahir Dar City, Ethiopia: an application of extended parallel process model

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic causes major morbidity and mortality in the world. Timely behavioral response assessment of the community is important to shape the next effective interventions and risk communication strategies to adopt preventive behavior. Hence, this study aimed to assess behavioral responses for facemask-use messages to prevent COVID-19 and its predictors among residents of Bahir Dar City, Ethiopia, 2021 by using the Extended Parallel Process Model.  METHODS: A community-based cross-sectional study was conducted with the guide of the Extended Parallel Process Model in Bahir Dar city from March 9 to April 9, 2021. A multistage sampling technique was used, and data was collected through a face-to-face interviewer-administered questionnaire using Epicollect5. Descriptive statistics and Binary logistic regression were computed using SPSS V.25. Variable with P < 0.25 in the bivariable analysis was a candidate for multivariable analysis to control confounding effect. In multivariable analysis, variables with P < 0.05 were considered statistically significant and the result was presented using an adjusted odd ratio (AOR) with a 95% confidence interval (CI).

RESULTS

A total of 616 participants with a response rate of 97.1% were included. Of the total participants, 229(37.2%) were in the danger control response. The behavioral response was affected by Occupational status [AOR (95%CI) 3.53(1.67-7.46)], the number of people living together [AOR (95%CI) 2.62(1.28-5.39)], self-control [AOR (95%CI) 1.14(1.05-1.25)], a friend for the preferred source of information [AOR (95%CI) 5.18(3.22-8.33)] and printed materials for the preferred channel [AOR (95%CI) 2.14(1.35-3.43)].

CONCLUSION

Above one-third of the participants were in the danger control response. Occupational status, number of people living together, self-control, a friend for the preferred source of information, and printed materials for the preferred channel were independent predictors of resident behavioral response to the use of facemasks. Policymakers should consider students and people who live alone. Message developers should use a friendly person to transmit messages and should prepare printed materials. Activities and strategies should also focus on self-control and perceived efficacy without ignoring the perceived threat.

Two-handed facemask technique effectively causes hyperventilation in electroconvulsive therapy: an observational study

BACKGROUND

Electroconvulsive therapy (ECT) remains the mainstay treatment option for patients with psychiatric diseases, such as severe depression. Although various anesthetic techniques provide adequate therapeutic seizures, hyperventilation is a useful adjunct to augment seizure duration and improve seizure quality. We investigated how to efficiently use a facemask to accomplish protocolized hyperventilation and evaluate its effect on ECT seizure.

METHODS

We studied 60 patients aged ≥18 years who underwent ECT. The patients were divided into two groups according to the technique of facemask ventilation used: the one-handed (n = 30) and two-handed (n = 30) groups. Following anesthesia induction under preoxygenation conditions, hyperventilation induced hypocapnia in the one-handed facemask group with manual bag ventilation was compared to that in the two-handed facemask group with assisted pressure-controlled ventilation. Ictal and peri-ictal electroencephalogram parameters and cardiovascular responses were monitored and compared between the one-handed and two-handed groups.

RESULTS

The two-handed technique demonstrated better electroencephalogram regularity and minimized cardiovascular stress compared to the one-handed technique. These conclusions come from the fact that the one-handed technique induced a substantial volume of leaks around the facemask (201.7 ± 98.6 mL/breath), whereas minimal leaks (25.8 ± 44.6 mL/breath) with stabler and higher ventilation rate led to greater inhaled minute ventilation in the two-handed group (the one-handed group, 9.52 ± 3.94 L/min; the two-handed group, 11.95 ± 2.29 L/min; p <  0.005). At the end of ECT treatment, all parameters of blood pressure and heart rate increased significantly in both groups equally, with lower SpO₂ and more ST-segment depression on the electrocardiogram in the one-handed group. Comparing baseline values before anesthesia, ECT treatment significantly depressed ST-segment in both groups, while the degree of depression in ST-segment increased significantly in the one-handed group compared to that in the two-handed group.

CONCLUSIONS

End-tidal carbon dioxide monitoring for hyperventilation can reliably ensure hypocapnia only in the two-handed group. In ECT, the two-handed technique assisted by pressure-controlled ventilation is an effective and practical method for hyperventilation to induce adequate therapeutic seizures. While, the two-handed group with sufficient preoxygenation did not cause more cardiovascular stress than the one-handed group.

TRIAL REGISTRATION

UMIN Clinical Trials Registry 000046544, Date of registration 05/01/2022.

Long-term skeletal and dentoalveolar effects of hybrid rapid maxillary expansion and facemask treatment in growing skeletal Class III patients: a retrospective follow-up study

BACKGROUND

Regardless of the treatment protocol, stability in Class III patients always represents a major concern. The aim of this study was to assess the short and long-term skeletal and dentoalveolar modifications in a group of class III patients treated with hybrid rapid maxillary expander (RME) and facemask (FM). Indeed, no long-term studies have been conducted yet with the objective of evaluating the effects of this kind of approach when applied to patients who have already gone thought their peak of growth.

MATERIAL AND METHODS

27 patients with skeletal Class III malocclusion were treated using hybrid RME according to alternating rapid maxillary expansion and constriction (ALT-RAMEC) protocol, followed by 4 months of facemask therapy. After the orthopaedic phase, each patient underwent orthodontic treatment with fixed multibracket appliances. A mean follow-up of 7 years, 10 months was performed. Pre-treatment (TO), post-treatment (T1) and follow up (T2) cephalometric tracing were analysed, comparing dental and skeletal measurements.

RESULTS

Point A advanced by a mean of 3.5 mm with respect to VerT, then relapsed by 0.7 in the post-facemask period, thereby yielding of a mean advancement of 2.7 at T2. The sagittal relationship significantly changed after RME + facemask protraction (3.8° of ANB and 5.189 mm of Wits). Although both Wits and ANB values worsened over time, the improvement from T0 is still appreciable at T2.

CONCLUSION

Despite the physiological relapse due to mandibular growth, the long-term cephalometric follow-up confirms the maintenance of all positive outcomes of the previous orthopaedic treatment with hybrid RME and facemask.

Perception and Concerns about the Use of Gloves, Facemask, and HIV Discriminatory Attitude of Children attending Dental Clinics in Southern Nigeria

INTRODUCTION

The use of face masks and gloves can prevent possible cross infection between dental patients and health care practitioners.

AIM

The study identified the perception of paediatric dental patients on the need for dentists to use face masks and gloves; and their attitude towards using the same clinic with paediatric dental patients living with HIV.

METHODS

This was a cross sectional study that recruited 438 children aged 8-15 years attending three paediatric dental clinics located in Southern Nigeria.

STATISTICAL ANALYSIS

The dependent variables were perception of cross infection control and attitude towards children living with HIV. The independent variables were age, sex, socioeconomic status and location of clinic. Chi-square analysis was conducted to determine the associations between the dependent and independent variables. Logistic regression analysis was also conducted to assess the effect size of the associations between the dependent and independent variables. The level of statistical significance was inferred at P < 0.05.

RESULTS

Majority of the respondents agreed that it was necessary to wear gloves (98.6%) and facemasks (88.1%) during patients' management. More females 62(28.2%) than males 38(17.4%) assumed gloves were used by dentists to protect themselves from patients' bad breath (p=0.007). More children from Benin 97(64.2%) were aware that face masks protect the dentists and the patients (p=0.004), and a few believed that it is embarrassing to patients for dentists to wear facemasks (p=0.001). More children 102(70.8%) from Ile-Ife perceived that face masks protects from bad breath (p=0.004).Children less than 10 years (AOR: 0.85; 95% CI: 0.42-1.70; p=0.64), with high socioeconomic status (AOR: 0.90; 95% CI:0.53-1.52; p=0.70) and children aged 10 to 14 years (AOR: 0.85; 95% CI: 0.44-1.63; p=0.62), in the middle socioeconomic status (AOR: 0.72; 95% CI: 0.39-1.33; p=0.30) were less willing to use the dental clinic alongside children living with HIV.

CONCLUSION

There were sex, and clinic location disparity in the perception and attitude of children towards the use of Personal Protective Equipment and the use of the dental clinic alongside children living with HIV.

Saving 80% Polypropylene in Facemasks by Laser-Assisted Melt-Blown Nanofibers

The ongoing coronavirus (COVID-19) pandemic requires enormous production of facemasks and related personal protection materials, thereby increasing the amount of nondegradable plastic waste. The core material for facemasks is melt-blown polypropylene (PP) fiber. Each disposable facemask consumes ∼0.7 g of PP fibers, resulting in annual global consumption and disposal of more than 1 150 000 tons of PP fibers annually. Herein, we developed a laser-assisted melt-blown (LAMB) technique to manufacture PP nanofibers with a quality factor of 0.17 Pa^-1 and significantly reduced the filter's weight. We demonstrated that a standard surgical facemask could be made with only 0.13 g of PP nanofibers, saving approximately 80% of the PP materials used in commercial facemasks. Theoretical analysis and modeling were also conducted to understand the LAMB process. Importantly, nanofibers can be easily scaled up for mass production by upgrading traditional melt blown line with scanning laser-assisted melt-blown (SLAMB).

Occurrence of COVID-19 personal protective equipment (PPE) litters along the eastern coast of Palawan Island, Philippines

The emergence of the COVID-19 pandemic has caused worldwide health constraints. This study was conducted to establish a baseline monitoring survey to describe the distribution of PPE litters during the COVID-19 pandemic in the province of Palawan, Philippines. A total of 386 COVID-19-related PPE items were present in 83 % of coastal sampling sites with over a cumulative area of 48,200 m², with a density of 8 × 10^-3 items m^-2. The facemask (98 %; n = 377) was the primary type of PPE, followed by face shield (2 %; n = 9). Meanwhile, the daily density of PPE litters in San Manuel, Puerto Princesa ranged from 0 to 9.9 × 10^-2 items m^-2, with a mean density of 8 × 10^-3 items m^-2. The accumulation rates of PPE items ranged from 3.27 × 10^-1 items to 1.143 items d^-1, with an average rate of 7.29 × 10^-1 items d^-1.

Face masks can reduce frequency of face touching: An observational crossover study

BACKGROUND

The purpose of this study is to analyze face touching patterns with and without face mask.

METHODS

The behavior of face touching with and without a mask during an interview was assessed in forty individuals. The frequency of touching in different areas of the face covered by the mask was compared to areas not covered by the face mask.

RESULTS

There was an increase in the number of individuals who touched the hair and the eye, when they were not wearing the mask. There was an increase in the number of touches on the lips and hair when individuals were not wearing the face mask. When analysing the area covered by face mask, no difference was observed on the number of touches while using or not using masks. However, when area not covered by face mask was analysed, higher number of touches in individuals without masks was observed when compared to individuals wearing masks.

CONCLUSION

The use of face mask can reduce or change the face touching patterns in normal individuals, especially in areas not covered by the mask. The use of face mask can possibly reduce the chances of being infected by auto-inoculation.

Uncertainty analysis of facemasks in mitigating SARS-CoV-2 transmission

In the context of global spread of coronavirus disease 2019 (COVID-19) caused by a novel coronavirus (SARS-CoV-2), there is a controversial issue on whether the use of facemasks is promising to control or mitigate the COVID-19 transmission. This study modeled the SARS-CoV-2 transmission process and analyzed the ability of surgical mask and N95 in reducing the infection risk with Sobol's analysis. Two documented outbreaks of COVID-19 with no involvers wearing face masks were reviewed in a restaurant in Guangzhou (China) and a choir rehearsal in Mount Vernon (USA), suggesting that the proposed model can be well validated when airborne transmission is assumed to dominate the virus transmission indoors. Subsequently, the uncertainty analysis of the protection efficiency of N95 and surgical mask were conducted with Monte Carlo simulations, with three main findings: (1) the uncertainty in infection risk is primarily apportioned by respiratory activities, virus dynamics, environment factors and individual exposures; (2) wearing masks can effectively reduce the SARS-CoV-2 infection risk to an acceptable level (< 10^-3) by at least two orders of magnitude; (3) faceseal leakage can reduce protection efficiency by approximately 4% when the infector is speaking or coughing, and by approximately 28% when the infector is sneezing. This work indicates the effectiveness of non-pharmaceutical interventions during the pandemic, and implies the importance of the synergistic studies of medicine, environment, social policies and strategies, etc., on reducing hazards and risks of the pandemic.

Fabrication of a highly protective 3D-printed mask and evaluation of its viral filtration efficiency using a human head mannequin

Facemasks are one of the most effective and low-cost prophylactics for COVID-19. In the spring 2020, when a severe shortage of facemasks occurred worldwide, various types of 3D-printed masks were designed and proposed. However, the protective effects conferred by most of these masks were not experimentally evaluated. Here, we provide a new simple design of 3D-printed mask and evaluate its protective effect in a viral filtration test using a human head mannequin. The developed mask can be constructed with a low-cost 3D printer, with an approximate production cost of US $4. This mask has three parts: the main part, wearing parts, and a piece of non-woven fabric filter. The volume of the filter, which needs to be changed daily, was reduced to approximately 1/10 of that of commercially available surgical masks used in this study. The developed mask is fabricated from polylactic acid, a biodegradable plastic, and its surface contour contacting the face may be adjusted after softening the material with hot water at 60-80°C. The viral filtration efficiency of the developed mask was found to be over 80%. This performance is better than that of commercially available facemasks, such as surgical masks and cloth masks, and equal to those of KN95 and KF94.

Is wearing a face mask associated with symptomatic dry eye disease among medical students during the COVID-19 era? An online survey

Background

Coronavirus disease 2019 has necessitate the routine use of masks worldwide. This study assessed the relationship between wearing a facemask and dry eye disease (DED) among a sample of medical students in Jordan.

Methods

This cross-sectional online survey enrolled medical students from all medical schools in Jordan. The questionnaire, which was shared via social media platforms, assessed sociodemographic information, ocular and medical history, facemask-wearing habits, the use of ocular devices, and the relationship with ocular discomfort. The ocular surface disease index (OSDI) questionnaire was also administered to quantify DED symptoms.

Results

A total of 1,219 students participated in this study. In total, 58.3% participants were females, and 52% were in the clinical science years. Symptomatic DED was found in 71.7% of participants. Female sex, basic science years, allergy reporting, and spending more than 6 h looking at screens were significantly associated with symptomatic DED.

Conclusion

Wearing a facemask was not significantly associated with symptomatic DED. Further studies are needed to investigate the effect of wearing a facemask on the ocular surface.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-022-02377-z.

Face masks have emotion-dependent dissociable effects on accuracy and confidence in identifying facial expressions of emotion

The coronavirus pandemic has resulted in increased use of face masks worldwide. Here, we examined the effect of wearing a face mask on the ability to recognise facial expressions of emotion. In a within-subjects design, 100 UK-based undergraduate students were shown facial expressions of anger, disgust, fear, happiness, sadness, and neutral expression; these were either posed with or without a face mask, or with a face mask artificially imposed onto them. Participants identified the emotion portrayed in the photographs from a fixed choice array of answers and rated their confidence in their selection. While overall accuracy was higher without than with masks, the effect varied across emotions, with a clear advantage without masks in disgust, happiness, and sadness; no effect for neutral, and lower accuracy without masks for anger and fear. In contrast, confidence was generally higher without masks, with the effect clear for all emotions other than anger. These results confirm that emotion recognition is affected by face mask wearing, but reveal that the effect depends on the emotion being displayed—with this emotion-dependence not reflected in subjects’ confidence. The disparity between the effects of mask wearing on different emotions and the failure of this to be reflected in confidence ratings suggests that mask wearing not only effects emotion recognition, but may also create biases in the perception of facial expressions of emotion of which perceivers are unaware. In addition, the similarity of results between the Imposed Mask and Posed Mask conditions suggests that prior research using artificially imposed masks has not been deleteriously affected by the use of this manipulation.

Widespread occurrence of phthalate and non-phthalate plasticizers in single-use facemasks collected in the United States

Single-use or disposable facemasks have been widely used by the public for personal protection against the spread of COVID-19. The majority of disposable facemasks are made of synthetic polymers such as polypropylene, polyethylene terephthalate (as polyester), and polystyrene, and could therefore be a source of human exposure to plasticizers that are incorporated into these polymers during production. Little is known, however, about the occurrence of plasticizers in facemasks. In this study, we determined the concentrations of nine phthalate diesters and six non-phthalate plasticizers in 66 facemasks purchased in the United States. Among phthalate diesters, dibutyl phthalate, di(2-ethylhexyl)phthalate, di-iso-butyl phthalate, and butyl benzyl phthalate were found in all facemask samples, at median concentrations of 486, 397, 254, and 92 ng/g, respectively. Among non-phthalate plasticizers, dibutyl sebacate (median: 3390 ng/g) and di(2-ethylhexyl)adipate (352 ng/g) were found at notable concentrations. Inhalation exposure to select phthalate and non-phthalate plasticizers from the use of facemasks was estimated to range from 0.1 to 3.1 and 3.5 to 151 ng/kg-bw/d, respectively. To our knowledge, this is the first study to report the occurrence of phthalate and non-phthalate plasticizers in facemasks collected from the United States.

Easing or tightening control strategies: determination of COVID-19 parameters for an agent-based model

Some agent-based models have been developed to estimate the spread progression of coronavirus disease 2019 (COVID-19) and to evaluate strategies aimed to control the outbreak of the infectious disease. Nonetheless, COVID-19 parameter estimation methods are limited to observational epidemiologic studies which are essentially aggregated models. We propose a mathematical structure to determine parameters of agent-based models accounting for the mutual effects of parameters. We then use the agent-based model to assess the extent to which different control strategies can intervene the transmission of COVID-19. Easing social distancing restrictions, opening businesses, speed of enforcing control strategies, quarantining family members of isolated cases on the disease progression and encouraging the use of facemask are the strategies assessed in this study. We estimate the social distancing compliance level in Sydney greater metropolitan area and then elaborate the consequences of moderating the compliance level in the disease suppression. We also show that social distancing and facemask usage are complementary and discuss their interactive effects in detail.

Comparison of facemask therapy effects using skeletal and tooth-borne anchorage

OBJECTIVES

To investigate long-term outcomes of dentoskeletal changes induced by facemask therapy using skeletal anchorage in Class III patients and compare them to those of conventional tooth-borne anchorage.

MATERIALS AND METHODS

This retrospective study included 20 patients who received facemask (FM) therapy with miniplates as anchorage for maxillary protraction (Miniplate/FM group, 10.6 ± 1.1 years old [mean ± SD]) and 23 patients who were treated with facemask with rapid maxillary expander (RME/FM group, 10.0 ± 1.5 years old [mean ± SD]). Dentoskeletal changes were evaluated using lateral cephalograms at pretreatment (T1), after facemask therapy (T2), and at the post-pubertal stage (T3). Cephalometric changes were compared between groups and clinical success rates at T3 were evaluated.

RESULTS

SNA and A to N perpendicular to FH increased significantly more in the Miniplate/FM group than in the RME/FM group when comparing short-term effects of facemask therapy (T1-T2). ANB, Wits appraisal, Angle of convexity, mandibular plane angle, and overjet decreased significantly more in the RME/FM group than in the Miniplate/FM group after facemask therapy (T2-T3). A more favorable intermaxillary relationship was observed in the Miniplate/FM group than in the RME/FM group in long-term observations (T1-T3). Clinical success rate at T3 was 95% in the Miniplate/FM group and 85% in the RME/FM group.

CONCLUSIONS

Facemask therapy with skeletal anchorage showed a greater advancement of the maxilla and more favorable stability for correction of Class III malocclusion in the long-term than conventional facemask therapy with tooth-borne anchorage.

A retrospective long-term comparison of early RME-facemask versus late Hybrid-Hyrax, alt-RAMEC and miniscrew-supported intraoral elastics in growing Class III patients

OBJECTIVE

To compare the long-term dentoskeletal effects of early treatment with banded or bonded RME (Rapid Maxillary Expansion)-Face Mask (RME-FM) versus late treatment with bonded Hybrid-Hyrax, alt-RAMEC (Alternate Rapid Maxillary Expansion and Contraction) and intraoral Class III elastics anchored to miniscrew-reinforced-Lower-lingual-Arch (alt-RAMEC-HH-LLA) in growing, maxillary retrognathic patients.

MATERIALS AND METHODS

Two groups were matched at long-term follow-up retrospectively. Patients received either early RME-FM (n=16, 5 males, 11 females, age T1: 6.5±0.9 years, age T2: 15.8±2.5 years) or late alt-RAMEC-HH-LLA (n=15, 7 males, 8 females, age T1: 12.52±0.94 years, age T2: 16.8±0.9 years). Total follow-up was 9.2±2.3 years and 4.2±0.2 years respectively, including fixed appliances to compete treatment.

RESULTS

Both treatments resulted in Class III correction except one unsuccessful case of alt-RAMEC-HH-LLA. Active maxillary protraction was 1.6±0.5years with RME-FM and 0.5 years with alt-RAMEC-HH-LLA being significantly shorter (P<0.001). Values at T2 estimation with multivariate linear regression for correlated multiple outcomes, conditional on baseline estimates, age and sex showed alt-RAMEC-HH-LLA inducing significantly more retroclined lower incisors (mean: -6.11°; 95%CI: -10.66, -1.57; P=0.01), less overbite (mean: -1.28mm; 95%CI: -1.79, -0.761; P<0.001), less maxillo (Co-A)- (mean: -4.54mm; 95%CI: -7.91, -1.16; P=0.01) mandibular (Co-Gn) (mean: -10.5mm; 95%CI: -17.45, -3.55; P=0.003) projections/size, more open gonial angle (mean: 4.93°; 95%CI: 2.27, 7.59; P<0.001), and less S-N length (mean: -5.04mm; 95%CI: -6.57, -3.51; P<0.001).

CONCLUSIONS

Patients treated with either early RME-FM or late Alt-RAMEC-HH-LLA had comparable overall post-pubertal skeletal and overjet corrections. However, the late Alt-RAMEC-HH-LLA showed less correction of dentoalveolar compensations and in particular of the mandibular incisors. The overbite, maxillary and mandibular projection and size were lower and the gonial angle was more open.

Three-dimensional oropharyngeal airway changes after facemask therapy using low-dose computed tomography: a clinical trial with a retrospectively collected control group

Aims

This study aimed to evaluate the short-term oropharyngeal airway volumetric changes in growing Class III maxillary-deficient patients treated by facemask without expansion compared with untreated Class III controls, using low-dose computed tomography.

Methods

Eighteen maxillary-deficient children (9 boys, nine girls) with a mean age of 7.81 ± 0.84 years were treated with maxillary bonded bite block and facemask (FM). Pre- (T1) and post-treatment (T2) low-dose CT images were acquired. Sixteen untreated Class III patients with a mean age of 7.03 ± 0.56 years had previously two low-dose CT scans within a one year of follow-up. Volumetric and minimal cross-sectional area measurements were obtained to assess the oropharyngeal airway changes. Quantitative mean, minimum, and maximum displacement of superimposed 3D models were estimated from a point-based analysis. Paired-samples t-tests were used for the intragroup comparisons, and an independent samples t-test and the Mann–Whitney U tests were carried out for the intergroup comparisons.

Results

A statistically significant increase in the total and retropalatal volumes oropharyngeal airway volume were observed in the control group (302.23 ± 345.58 and 145.73 ± 189.22 mm³, respectively). In the FM group, statistically significant increases in the total and retropalatal volumes were observed (738.86 ± 1109.37 mm³ and 388.63 ± 491.44 mm³, respectively). However, no statistically significant differences were found between the two groups, except for the maximum part analysis which was significantly greater in the FM group (p = 0.007).

Conclusions

FM therapy appeared to have no additional effects on the oropharyngeal airway other than those induced by growth.

Facemasks during aerobic exercise: Implications for cardiac rehabilitation programs during the Covid-19 pandemic

Introduction and objectives

During the COVID-19 pandemic, among the safety measures adopted, use of facemasks during exercise training sessions in cardiac rehabilitation programs raised concerns regarding possible detrimental effects on exercise capacity. Our study examined the cardiorespiratory impact of wearing two types of the most common facemasks during treadmill aerobic training.

Methods

Twelve healthy health professionals completed three trials of a symptom-limited Bruce treadmill protocol: Without a mask, with a surgical mask and with a respirator. Perceived exertion and dyspnea were evaluated with the Borg Scale of Perceived Exertion and the Borg Dyspnea Scale, respectively. Blood pressure, heart rate and arterial oxygen saturation (SpO2) were measured at each 3-minute stage.

Results

Using a surgical mask or a respirator resulted in a shorter duration of exercise testing. At peak capacity, using a respirator resulted in higher levels of dyspnea and perceived exertion compared to not wearing a facemask. A significant drop in SpO2 was present at the end of exercise testing only when using a respirator. There were no differences in either chronotropic or blood pressure responses between testing conditions.

Conclusions

Professionals involved in cardiac rehabilitation should be aware of the cardiorespiratory impact of facemasks. Future studies should assess whether exposure to these conditions may impact on the overall results of contemporary cardiac rehabilitation programs.

What do masks mask? A study on transdermal CO2 monitoring

Medical professionals have complained of extreme discomfort and fatigue from continuous wearing of N95 respirators (N95) overlaid with surgical masks (SM) and face shields (FS) during COVID-19 pandemic. However, there are no reports on the effect of face coverings on transdermal CO₂ (TrCO₂) levels (a measure of blood CO₂) during moderate activity. In this study, real-time monitoring of TrCO₂, heart rate and skin surface temperature was conducted for six subjects aged 20-59 years with and without wearing personal protective equipment (PPE). We initially studied the effect of wearing PPE (N95+SM+FS) at rest. Then, the effect of moderate stepping/walking activity (120 steps per minute for 60 min) while wearing PPE was evaluated. In addition, we investigated the effect of exercising intensity with different masks. We observed a significant difference (p < 0.0001) in TrCO₂ levels between without and with PPE during moderate exercise, but not while resting. TrCO₂ levels were correlated to exercise intensity independently with masking condition and breathability of masks. For the first time, we present data showing that a properly fitting N95 worn along with SM and FS consistently leads to elevated TrCO₂ under moderate exertion, which could contribute to fatigue over long-term use.

Factors affecting willingness to comply with public health measures during the pandemic among sub-Sahara Africans

Background

The unprecedented outbreak of coronavirus disease (COVID-19) drastically spread worldwide, resulting in extraordinary measures put in place in various countries including Sub Saharan Africa (SSA) countries.

Objective

To assess the factors associated with compliance with the public health measures imposed by various SSA countries.

Method

Cross sectional study using self-administered surveys distributed on social media platforms between April 18th and May 16th, 2020, corresponding with the mandatory lockdown period in most SSA countries. Multivariate analysis examined the associated factors.

Results

The prevalence of hand hygiene, quarantine, self isolation practices, wearing of face mask and attending large gatherings during COVID-19 were 94%, 39%, 31%, 64% and 14%, respectively. In multivariate models, older age 49+ years: adjusted OR 2.13, 95%CI 1.22,3.71), females (OR 1.41,95%CI 1.03,1.93), Central African countries (OR 3.73,95%CI 2.02,6.87) were associated with wearing face mask. Living alone (aOR 1.52,95%CI 1.04,2.24) during the lockdown was associated with avoiding large gatherings including religious events. Female respondents (aOR 1.61, 95%CI 1.30, 2.00), married (aOR 1.71,95%CI 1.33,2.21) and unemployed (aOR 1.62,95%CI 1.25,2.09) SSAs were more likely to practice self-quarantine measures.

Conclusion

The low prevalence of mitigation practices suggest the need for targeted education campaign programs to sensitise the population

Does Facemask Impact Diagnostic During Pulmonary Auscultation?

Facemasks have been widely used in hospitals, especially since the emergence of the coronavirus 2019 (COVID-19) pandemic, often severely affecting respiratory functions. Masks protect patients from contagious airborne transmission, and are thus more specifically important for chronic respiratory disease (CRD) patients. However, masks also increase air resistance and thus work of breathing, which may impact pulmonary auscultation and diagnostic acuity, the primary respiratory examination. This study is the first to assess the impact of facemasks on clinical auscultation diagnostic. Lung sounds from 29 patients were digitally recorded using an electronic stethoscope. For each patient, one recording was taken wearing a surgical mask and one without. Recorded signals were segmented in breath cycles using an autocorrelation algorithm. In total, 87 breath cycles were identified from sounds with mask, and 82 without mask. Time-frequency analysis of the signals was used to extract comparison features such as peak frequency, median frequency, band power, or spectral integration. All the features extracted in frequency content, its evolution, or power did not significantly differ between respiratory cycles with or without mask. This early stage study thus suggests minor impact on clinical diagnostic outcomes in pulmonary auscultation. However, further analysis is necessary such as on adventitious sounds characteristics differences with or without mask, to determine if facemask could lead to no discernible diagnostic outcome in clinical practice.

Retrospective analysis of interventions to epidemics using dynamic simulation of population behavior

Retrospective analyses of interventions to epidemics, in which the effectiveness of strategies implemented are compared to hypothetical alternatives, are valuable for performing the cost-benefit calculations necessary to optimize infection countermeasures. SIR (susceptible-infected-removed) models are useful in this regard but are limited by the challenge of deciding how and when to update the numerous parameters as the epidemic changes in response to population behaviors. Behaviors of particular interest include facemask adoption (at various levels) and social distancing. We present a method that uses a "dynamic spread function" to systematically capture the continuous variation in the population behavior and the gradual change in infection evolution, resulting from interventions. No parameter updates are made by the user. We use the tool to quantify the reduction in infection rate realizable from the population of New York City adopting different facemask strategies during COVID-19. Assuming a baseline facemask of 67% filtration efficiency, calculations show that increasing the efficiency to 80% could have reduced the roughly 5000 new infections per day occurring at the peak of the epidemic to around 4000. Population behavior that may not be varied as part of the retrospective analysis, such as social distancing in a facemask analysis, are automatically captured as part of the calibration of the dynamic spread function.

Technical note: Impact of face covering on aerosol transport patterns during coughing and sneezing

COVID-19 is spread via different routes, including virus-laden airborne particles generated by human respiratory activities. In addition to large droplets, coughing and sneezing produce a lot of small aerosol particles. While face coverings are believed to reduce the aerosol transmission, information about their outward effectiveness is limited. Here, we determined the aerosol concentration patterns around a coughing and sneezing manikin and established spatial zones representing specific elevations of the aerosol concentration relative to the background. Real-time measurements of sub-micrometer aerosol particles were performed in the vicinity of the manikin. The tests were carried out without any face covering and with three different types of face covers: a safety faceshield, low-efficiency facemask and high-efficiency surgical mask. With no face covering, the simulated coughing and sneezing created a powerful forward-propagating fine aerosol flow. At 6 ft forward from the manikin head, the aerosol concentration was still 20-fold above the background. Adding a face covering reconfigured the forward-directed aerosol transmission pattern. The tested face coverings were found capable of mitigating the risk of coronavirus transmission; their effectiveness is dependent on the protective device. The outward leakage associated with a specific face covering was shown to be a major determinant of the exposure level for a person standing or seating next to or behind the coughing or sneezing "spreader" in a bus/train/aircraft/auditorium setting. Along with reports recently published in the literature, the study findings help assess the infectious dose and ultimately health risk for persons located within a 6-ft radius around the "spreader."

Natural vaccines accumulated in facemasks during COVID-19: Underappreciated role of facial masking

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a causal agent behind coronavirus disease 2019 (COVID-19). Despite promising developments in therapeutic and preventive avenues, the importance of facial masking is a key factor for the protective measures among exposed human populations. Preclinical and clinical data on the importance of facial masking concerning asymptomatic over symptomatic COVID-19 cases is limited. The recent introduction of the concept of SARS-CoV-2 associated molecular particle patterns (SAMPPs) as a natural vaccine has opened new avenues for the comprehensive development of immunity. To take this further, the scope of natural vaccines accumulated in facemasks during facial masking needs to be highlighted that may directly or indirectly contribute to building adaptive immunity among human populations. This paper attempts to discuss the underappreciated contributions of facial masking in the management of COVID-19 at the global level.

Are facemasks a priority for all staff in theatre to prevent surgical site infections during shortages of supply? A systematic review and meta-analysis

BACKGROUND

The provision of facemasks must be prioritised when supplies are interrupted. These include supplies to operating rooms. The aim of this review is to evaluate the available evidence to determine the relative priority for the provision of facemasks in operating rooms to prevent surgical site infection.

METHODS

A systematic search of OVID Medline, Embase & Cochrane Central was completed. Candidate full-text articles were identified and analysed by two reviewers who also assessed risk of bias.

FINDINGS

Six studies were identified that described infections with and without facemask usage. The pooled effect of not wearing facemasks was a risk ratio for infection of 0.77 (0.62-0.97) in favour of not wearing masks. Only one case-controlled study evaluated facemask usage in implant surgery and demonstrated an odds ratio for developing infection of 3.34 (95% CI 1.94-5.74) if facemasks were not worn by the operating surgeon. Four studies collected microbiological cultures during periods in surgery with or without facemasks. Two demonstrated an increase in colony forming units in surgery where the wound was directly below the surgeon. One study showed equivocal results when masks were worn, and one was terminated early limiting interpretation.

CONCLUSION

The use of facemasks by scrubbed staff during implant surgery should be mandatory to prevent infection. We recommend the use of facemasks by all scrubbed staff during other forms of surgery to protect the patient and staff, but the supporting evidence is weak. There is insufficient evidence to show that non-scrubbed staff must wear masks during surgery.

Potential biodegradable face mask to counter environmental impact of Covid-19

On the eve of the outbreak of the COVID-19 pandemic, there is a tremendous increase in the production of facemasks across the world. The primary raw materials for the manufacturing of the facemasks are non-biodegradable synthetic polymers derived from petrochemicals. Disposal of these synthetic facemasks increases waste-load in the environment causing severe ecological issues for flora and fauna. The synthesis processes of the polymers from the petrochemical by-products were also not eco-friendly, which releases huge greenhouse and harmful gases. Therefore, many research organizations and entrepreneurs realize the need for biodegradable facemasks to render similar performance as the existing non-biodegradable masks. The conventional textile fabrics made of natural fibers like cotton, flax, hemp, etc., can also be used to prepare facemasks with multiple layers in use for general protection. Such natural textile masks can be made anti-microbial by applying various herbal anti-microbial extracts like turmeric, neem, basil, aloe vera, etc. As porosity is the exclusive feature of the masks for arresting tiny viruses, the filter of the masks should have a pore size in the nanometre scale, and that can be achieved in nanomembrane manufactured by electrospinning technology. This article reviews the various scopes of electrospinning technology for the preparation of nanomembrane biomasks. Besides protecting us from the virus, the biomasks can be useful for skin healing, skincare, auto-fragrance, and organized cooling which are also discussed in this review article.

Universal use of surgical masks is tolerated and prevents respiratory viral infection in stem cell transplant recipients

Prevention of respiratory viral infection in stem cell transplant patients is important due to its high risk of adverse outcome. This single-centre, mixed methods study, conducted before the severe acute respiratory syndrome coronavirus-2 pandemic, explored the barriers and facilitators to a policy of universal mask use by visitors and healthcare workers, and examined the impact of the first year of introduction of the policy on respiratory viral infection rates compared with preceding years, adjusted for overall incidence. Education around universal mask use was highlighted as being particularly important in policy implementation. A significant decrease in respiratory viral infection was observed following introduction.

Behind the Mask: Emotion Recognition in Healthcare Students

Current widespread facemask usage profoundly impacts clinical practice and healthcare education where communicational dimensions are essential to the care and teaching processes. As part of a larger study, 208 medical and nursing students were randomly assigned to a masked vs unmasked version of the standardized facial emotion recognition task DANVA2. A significantly higher number of errors existed in the masked vs unmasked condition. Differences for happy, sad, and angry faces, but not for fearful faces, existed between conditions. Misinterpretation of facial emotions can severely affect doctor-patient and inter-professional communication in healthcare. Teaching communication in medical education must adapt to the current universal use of facemasks in professional settings.

Mid-term follow up effectiveness of facemask treatment in class III malocclusion: A systematic review

OBJECTIVE

This systematic review aims to investigate and summarize the mid-term effects and stability of the treatment with facemask appliance.

METHODS

Search without restrictions in five databases (Pubmed, Medline, Embase, Scopus, Cochrane Central Register of Controlled Trials) since inception and hand searching until March 2021 was conducted. Detailed search strategies were based on the PubMed strategy and adapted accordingly. Studies assessing the mid-term effects of facemask appliance, with a follow-up post-treatment period of more than 6 years or after the peak of pubertal growth, were to be included. The risk of bias in individual studies was assessed using the Cochrane guidelines for the RCT and the ROBINS-I tool for the non-RCT studies.

RESULTS

Five studies were finally considered eligible for inclusion (one RCT and four CCTs). According to the reported evidence, the mid-term success rate ranged from 62.7% to 100%. Mid-term success was identified with positive overjet as well as acceptable aesthetic and functional characteristics.

CONCLUSIONS

Class III malocclusion treated with facemask presents a high percentage of success in the mid-term follow-up period. The mid-term effects of facemask were stable for the maxilla, in terms of sagittal and anteroposterior dentoskeletal dimensions, and any kind of relapse is attributed to uncontainable residual growth of the mandible. However, considering the high risk of bias and the follow-up period limitations, more high-quality studies are necessary in order to achieve further clarification. Future research should be based also on identifying biomarkers to indicate likely treatment responses.

REGISTRATION NUMBER

PROSPERO: CRD42020179402.

Easing or tightening control strategies: determination of COVID-19 parameters for an agent-based model

Some agent-based models have been developed to estimate the spread progression of coronavirus disease 2019 (COVID-19) and to evaluate strategies aimed to control the outbreak of the infectious disease. Nonetheless, COVID-19 parameter estimation methods are limited to observational epidemiologic studies which are essentially aggregated models. We propose a mathematical structure to determine parameters of agent-based models accounting for the mutual effects of parameters. We then use the agent-based model to assess the extent to which different control strategies can intervene the transmission of COVID-19. Easing social distancing restrictions, opening businesses, speed of enforcing control strategies, quarantining family members of isolated cases on the disease progression and encouraging the use of facemask are the strategies assessed in this study. We estimate the social distancing compliance level in Sydney greater metropolitan area and then elaborate the consequences of moderating the compliance level in the disease suppression. We also show that social distancing and facemask usage are complementary and discuss their interactive effects in detail.

Treatment outcomes of various force applications in growing patients with skeletal Class III malocclusion

OBJECTIVES

To evaluate skeletal, dentoalveolar, and soft tissue changes between intraoral light force application and extraoral heavy force application in growing patients with skeletal Class III malocclusion.

MATERIALS AND

Methods: A retrospective study was conducted with pretreatment and posttreatment lateral cephalometric data from 50 subjects with skeletal Class III malocclusion. In the first group (15 boys, 10 girls; 8.67 ± 2.13 years old), each subject wore a biocreative horseshoe appliance (CHS) with two Class III elastics that exerted a force of 200 g. In the second group (13 boys, 12 girls; 8.96 ± 1.82 years old), each subject wore a Petit-type facemask and a lingual arch with hooks fixed to the maxillary arch with a total force of 700 g. Both groups of patients were instructed to wear the appliance approximately 14 hours a day, and 22 linear measurements and 8 angular measurements were evaluated. Changes of measurements from each group were compared by paired t-tests, considering a 5% significance level.

RESULTS

Forward growth of the maxilla, improvement of the maxilla-mandible relationship, and upper incisor flaring were achieved in both groups without any statistically significant difference between them. Lateral cephalometric analysis also showed that U1 exposure, IMPA (Angle between mandibular plane and mandibular incisor axis), FMIA (Angle between FH plan and mandibular incisor axis), and L1-APog (Angle formed by the intersection of tooth axis of lower incisor and A-Pog line, Distance from lower incisor edge to A-Pog line) showed statistically significant differences. Lower incisors were inclined lingually in the CHS group.

CONCLUSIONS

During treatment of skeletal Class III malocclusion, the CHS with light Class III intermaxillary elastics therapy exhibits similar orthopedic changes to the maxillary complex and more dental changes to the lower anterior teeth compared with facemask therapy.

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What are the sources of exposure in healthcare personnel with coronavirus disease 2019 infection?

In our facility, 25% of personnel with coronavirus disease 2019 (COVID-19) had a higher-risk exposure to an infected patient or co-worker and 14% reported a higher-risk exposure in the community. All higher-risk exposures to infected patients occurred on non-COVID-19 units, often when there was a delay in diagnosis because COVID-19 was not initially suspected. Higher-risk exposures to co-workers with COVID-19 often involved lapses in compliance with masking in nonpatient care areas such as nursing stations and staff work or break rooms.